WASHINGTON -- The chairman of the Senate Judiciary Committee announced plans Monday for his panel to start voting later this week on an assault weapons ban and other gun curbs, but that session is widely expected to be delayed a week.

When the votes occur, they will mark Congress' first in response to the Newtown, Conn., shooting deaths of 26 students and staff at an elementary school in December.

The bills largely follow President Barack Obama's proposals for limiting gun violence, which have been opposed by the National Rifle Association and generated little support from congressional Republicans.

Sen. Patrick Leahy, D-Vt., the committee chairman, said the panel would consider:

â€¢ A Leahy measure toughening federal penalties for illegal trafficking of guns, including up to 30-year sentences for people buying firearms they know will be used in crimes;

â€¢ A measure by Sen. Barbara Boxer, D-Calif., increasing federal grants for school safety measures such as installing surveillance equipment.

Leahy said the panel would also consider still evolving legislation expanding the requirement for federal background checks for gun purchases, which are now required only for transactions by federally licensed gun dealers. Requiring those checks for nearly all gun sales is a top Obama goal, and one that has received the broadest support by the public and in Congress.

The details of the bill are not yet complete as liberal Sen. Charles Schumer of New York, the No. 3 Senate Democratic leader, continues trying to reach a compromise with conservative Sen. Tom Coburn, R-Okla.

Judiciary committee rules allow senators to postpone announced legislative work for a week, a routine practice that Leahy and Senate aides of both parties have said they expect to occur this time. Beth Levine, spokeswoman for the panel's top Republican, Sen. Charles Grassley of Iowa, said it was uncertain if anyone would seek a delay and noted that "the bills don't appear to be ready for consideration."

Feinstein is chairing a Judiciary Committee hearing on Wednesday on her effort to ban assault weapons, a proposal that is given low odds of enactment because of opposition by many Republicans and resistance by some moderate Democrats. One scheduled witness is Dr. William Begg, an emergency room physician who helped treat victims of the Newtown shootings. Feinstein has said the public needs to know how gruesome assault weapons wounds can be.